I usually run with two DPS (me on my SMF warrior and one friend on his monk, or rogue depending on what he feels like playing) and a shaman healer from guild. We breeze through just about everything with that group. We've had some debate about how necessary it is for the shaman to be healing spec. He's said he might switch to a damage spec and see how that works next run.

Never tried that. Does it really improve your DPS that much ? I play my DK as blood too but only switch the weapon for fallen crusader runeforge.

IMO Blood DK and BrM moonk are the best "speed" tank for HC scenario. While protpaladin can take with him pure dps with no selfhealing without even watching their life bar. Have no warrior or bear in my friends sooo can't tell for them (and never run a PU group with one).

3 dps:
As a feral druid, I just use my PS proc's to heal anyone that isn't at 100% with Healing Touch. It usually ends up being myself though since I aggro just about everything with a RoR proc'd Thrash.